How much is to much in a water change?

[dustinw]

When you do a big water change in your opinion how much is to much? I've heard people say 20% is to big and people have said they do 50% water change. Just your thoughts.

 

[Stephanie11]

Subscribed

 

[Mike J.]

IMO 20% shouldn't be a problem at all. 50% is borderline and should only be done when necessary; like toxins or ammonia poisoning. JMO Some people change all their water when using NSW.

 

[Reefing Madness]

50% is not a big deal, as long as nothing gets exposed to air, live rock being the big one, then your all set, the majority of your bacteria is in the rock, not the water. Its not advisable to do to many 50% water changes in a row, then its gets dicey, but doint one large one a month is not a big deal.

 

[Ole Man]

I agree 50% is left for emergencies like toxins,phosphate,nitrate outbreaks but it also depends on your total water volume IMO..I have done both with no ill effects.JMO

 

[TriMax]

I have about 300g in two different tanks. I do about 100g water changes, each, when I do them. I am not very consistent, however. Well, I am very consistent when it come it being inconsistent.